The five new wells the American Samoa Power Authority has been working on since last year July are now at 90% says Matamua Katrina Mariner, ASPA’s Water and Wells Engineer.  Responding to Samoa News questions, Matamua stated the project had been proposed to locate and drill for new, good quality groundwater resources to ensure ASPA customers have  sufficient good water supply to enable them to lift the boil water notice that’s been effective for several years now.

“To date, six wells have been drilled and five have undergone pumping test procedures to calculate their sustainable yield,” she told Samoa News, adding that one well is still awaiting a pump test to calculate the recommended yield.

The five wells that have been drilled and pump tested will produce 955gpm out of the 1,000gpm that was projected for this project, hence we have achieved 95.5% of the targeted production from this project,” she stated.

She said ASPA needs a minimum of 2,000gpm for the Central System to replace the Groundwater Under Direct Influence of Surface Water (GUDI) wells which are supplying this system.  She noted that it is the GUDI wells which are the cause of the Boil Water Notice (BWN).

The five new wells will produce 955gpm and ASPA is also working hard to reduce Non Revenue Water (NRW), and more new wells will need to be drilled to provide at least another 1,000gpm to the Central system.

Matamua says a work plan to drill eight new wells has been submitted to USEPA for approval. Five of the new wells in this work plan will target the Eastern side of Tutuila, and these five wells will be directionally drilled with a new drill rig that is going through the ASPA procurement process. She stated that directional drilling is recommended for the Eastern side of Tutuila.

“A new work plan for water system improvement in the village of Aoa has also been submitted for funding to USEPA, and this proposal is currently under review,” she noted. A Scope of Work which proposes new wells in Manu’a is also currently under review by USEPA, and covers a new well in Ofu Island and a new well in Ta’u Island. ASPA continues to work with ASEPA in assisting and providing guidance in drilling said Matamua.

She told Samoa News that these new wells will improve water pressure and distribution to the Central Water System and that finding good water sources on the Eastern side of Tutuila Island will alleviate water quality, water pressure and supply problems on that side of the Island. They are also looking at drilling new wells in the Manu’a Islands.

Additional Water Sources will enable the shutdown of all GUDI wells and enable the lifting of the Boil Water Notice in the hydraulic zones affected on Tutuila, which they are targeting for 2016. She further told Samoa News the supporting projects assist ASPA’s drilling projects by helping collect data, synthesize information and enabling the ASPA hydrogeologist to use these as tools for proper groundwater engineering in order to come up with best solutions for groundwater drilling.

Matamua explained to Samoa News that ASPA is using the numeric software FEFLOW 6.1 to simulate groundwater dynamics for the new water wells. The first three wells that were drilled in the Five New Wells Drilling Project have been numerically modeled using pumping test results, field data, geologic and hydrometric data. These simulations will be validated once the new wells are connected to the system. She said the groundwater modeling for the other wells that were drilled are underway.

ASPA, UH AND WEATHER STATIONS

Matamua stated that ASPA is working together with the University of Hawaii (UH) to help with data collection, monitoring and information sharing. She said they are also working with UH to install weather stations on Tutuila Island which will collect rainfall, solar radiation, wind speed, humidity and temperature data. In the near future, there will also be an installation of stream gauges at selected stream locations to collect water level and discharge measurements.

“To date, three weather stations have been installed in selected areas. Selection of sites is based on ensuring a wide network distribution covering the Island. One more weather station will be installed on the top of Mt Alava this month. At the moment, stream gauge sighting is still ongoing.”